/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.lucene.spatial.geometry;

/**
 * Implementation of {@link GeoDistanceCalculator} that calculates distances as though the points are on a globe.
 */
public class ArcGeoDistanceCalculator implements GeoDistanceCalculator {

  /**
   * {@inheritDoc}
   */
  public double calculate(
      double sourceLatitude,
      double sourceLongitude,
      double targetLatitude,
      double targetLongitude,
      DistanceUnits units) {
    LatLng sourcePoint = new LatLng(sourceLatitude, sourceLongitude);
    LatLng targetPoint = new LatLng(targetLatitude, targetLongitude);
    return DistanceUnits.convert(sourcePoint.arcDistance(targetPoint, DistanceUnits.MILES), DistanceUnits.MILES, units);
  }
}
